April 11, 2024

To Jog Or To Walk (Between Interval Repeats), That Is The Question

Interval training is the most studied and most proven of all methods to boost fitness by increasing your vo2 max. But one question has been debated through the ages.

Should you jog between intervals (or, more accurately, between the hard repeats)? Or should you walk slowly, or even just stand in place until your next repeat? These are generally termed “active” vs “passive” recovery methods.

It’s tempting to quickly deduce that jogging between repeats should be superior, since it raises the overall intensity a smidgeon or two. On the other hand, a more passive recovery could allow you to run more or faster intervals, which is the point of the workout. So the question doesn’t resolve readily.

That’s why a recent systematic review and meta analysis set out to find an answer. The authors located 13 relevant studies that used passive recoveries, and 11 with active recoveries. Then they compared and contrasted the results of these 24 total studies.

Conclusion: “The applied recovery type (active or passive) during interval training seems not to affect the training-induced outcomes.” To put it simply, they found both methods roughly equivalent “in trained and untrained adults.”

This implies that, when doing interval training, you should concentrate on the length and pace of your repeats, and less so on the recovery method you use between repeats. More at Sports Medicine Open with free full text.

Loneliness & Lifespan--And Why They Are Linked

Here’s a fascinating new line of research that brings to mind all those studies indicating that “socialization” is a key ingredient in health and longevity, along with other basic habits like not smoking, exercise, diet, good sleep, etc. Here's one such study, a meta analysis.

It has always seemed a difficult to quantify/comprehend this socialization factor in the way that we understand exercise, cholesterol, blood pressure, and so on. Socialization has appeared murkier than other specific, biological measures. At least to me.

But what if socialization was simply a proxy for something else? Suppose it could be shown that socialization is linked to higher levels of exercise. Then we’d have something.

That’s one of the key findings from a new paper with meta-analysis titled “Life-course social participation and physical activity in midlife.” It followed more than 17,000 British citizens born during a single week in 1970, and revisited 9 times on the way to age 46. Those check-ins included 4 assessments of “social participation” and an objective measure of physical activity at age 46, using accelerometers (Fitbit-like instruments).

Result: The participants who were the most social also engaged in more physical activity.

Conclusion: “Our study provides empirical evidence on the importance of sustaining social participation at all ages over the life-course.” The association was particularly strong for moderate to vigorous physical activity, generally obtained from leisure-time exercise like running, cycling, and playing soccer. This association remained even after the researchers controlled “for a wide range of potential confounders.”

Also: “Given that increased physical activity is evidently linked to chronic disease prevention, our findings are of great importance in promoting ‘healthy aging’.” So be social, and keep moving. More at Frontiers in Psychology with free full text.

Sole Mates: Camille Herron’s Guide To Healthy Feet

I knew Camille Herron was a fantastic, record-breaking ultra runner. I didn’t know she was obsessive about good foot care during her long races. But it makes good sense. No one’s going to cover 500+ miles in 6 days, as she recently did, without getting a pedicure or two en route. 

Here Herron discusses and shows photos of her foot-health regimen for the recent Further race sponsored by Lululemon. She began by training exclusively in the recently developed Lululemon shoes that she planned to wear for 6 days. Practice makes perfect. She then had her “foot guru” tape her feet, especially her longer Morton’s toe.

During the race, when she wanted a “softer” feel from her shoes, she added a thin inner sole. She wore four pairs of shoes over 6 days, and also multiple pairs of high compression socks. 

Nothing could stop her feet from swelling with all the daily mileage. But Herron says: “My feet were the healthiest part of my body when I finished!” Any marathoner or ultra runner would be happy to say the same post race. She also showed a photo of how she laces her shoes for ultras. More at Instagram Run Camille with shoe-lacing photo.

4 Steps To Get Rid Of Tight Muscles

If you’ve never had a tight leg muscle after running or racing, congratulations. But also: Hey, now, you’re supposed to crank it up a bit every now and then. Which often leads to tight/sore muscles.

Every veteran runner has experienced tight muscles on multiple occasions, often after running a race quite a bit faster/longer than normal training efforts. This is the natural order of things.

But, of course, you want to get rid of that tightness as quickly as possible. And maybe figure out a way to prevent it next time around.

Many of us conclude that we haven’t been stretching or foam rolling enough. Maybe we try massage, ice, or the opposite--a warm bath with epsom salts.

If these work for you, that’s great. You’re in luck. But running physio Tom Goom thinks there’s a better way--in fact, 4 ways.

He recommends: 1) a recovery week with low training volume to resolve muscle fatigue; 2) testing your leg muscles when they feel strong again to determine if you need a specific strength training program; 3) easing into such a program if it’s necessary; and 4) a gradual return to your desired training level. More at Running Physio with a simple infographic.

Boost Your VO2 Max For Maximal Longevity

Dr. Peter Attia is author of the best-selling Outlive: The Science & Art of Longevity, and a popular podcaster and blogger as well. Lately he’s been writing a lot about the links between vo2 max and longevity. 

VO2 max is a simple, powerful measure of your fitness. There are two contributing factors to vo2 max: the amount of blood your heart can pump, and the amount your muscles can utilize. These are known as the “central” (heart) and peripheral (local muscles) factors. 

I think of vo2 max as my 5K time: It’s been going down for 50 years, because that’s what happens when you age, but it still places me above the 90th percentile among my peers. And I’m satisfied with that. 

Attia titles this first linkThe [almost] unbelievable effects of a high maximal aerobic capacity on all-cause mortality.”  He further states that “increasing VO2 max is associated with a monotonic risk reduction in cardiovascular mortality” and also “monotonic risk reduction of all-cause mortality (ACM) at any age.” 

I had to look up the meaning of monotonic. In this context, It means “always” or even “always increasing.” In other words, Attia believes vo2 max improves your longevity, and the higher your vo2 max, the greater the benefit.

A second Attia link provides greater explanation of the power of vo2 max by analyzing the results of this powerful paper titled “Association of Cardiorespiratory Fitness With Long-term Mortality Among Adults Undergoing Exercise Treadmill Testing.” It followed more than 122,000 adults for 8.4 years after each had taken a treadmill test to determine their vo2 max.

Result: “Cardiorespiratory fitness was inversely associated with all-cause mortality.” The higher your fitness, the lower your risk of death. 

Not only that, but “Extreme cardiorespiratory fitness was associated with the lowest all-cause mortality.” In other words, those who trained the most to achieve an extremely high vo2 max also lived the longest.

Attia notes, in addition, that the benefits derived when people lift themselves from low fitness to average fitness and above are greater than the benefits derived from Improving your smoking status, your diabetes, your blood pressure, and so on. 

This, he writes, “gives you a greater appreciation for how much improvement in mortality comes from improving your fitness.” On his podcast, Attia has also interviewed exercise, vo2 max, and marathon expert, Michael Joyner.

Careful About Those Post-Marathon Recovery Walks

You’re probably not planning to do much running in the days after your next marathon. And that’s a good thing. Better to give your body the full recovery it needs.

Instead, maybe you’re planning a leisurely saunter around Boston, London, Duluth, or wherever you’ll be. On a modest walk, you can visit a few of the local tourist highlights that everyone wants to see.

However, a new study indicates that even a simple stroll could increase your risk of post-marathon injury. And the explanation is simple, and common-sensical.

The marathon beats up your body, especially the quadriceps muscles. As a result, they don’t function normally for the next several days. Call this “neuromuscular fatigue.”

That’s not just a fancy name for “tired.” It means that you actually move differently--with “a significant decrease in peak knee flexion and an increase in peak hip internal rotation.”

Result: You have a greater chance of “developing patellofemoral PFPS pain,” ie, a knee injury. So, if you’re feeling the need for some post-marathon activity, it might be smart to substitute swimming or stationary bicycling for several days. Those have long been the preferred post-marathon-recovery exercises of experienced runners. More at J of Sports Sciences.

Strange But True: You Run As You Think

Here’s one of those “didn’t see that one coming” reports that I enjoy so much. It explores “the intriguing interplay between personality traits of individuals and their preferred movement patterns.” Okay, I’m hooked.

The paper is based on a branch of brain research called “embodied cognition.” This is defined as “a compelling theoretical framework in cognitive science that challenges conventional notions that divorce the mind from the body.”

When it comes to running, this means that your biomechanics aren’t simply a matter of how your legs and feet move over the ground. They’re also partially based on your “thinking-feeling.”

Researchers in this field use tools like the well known Myers-Briggs questionnaire. The MB characterizes people along four different dichotomies: extraversion-introversion, sensing-intuition, thinking-feeling, and judging-perceiving.

It has been shown, for example, that extroverted individuals tend to develop an “ideally aligned” posture with a relatively flat back, while introverts develop rounded shoulders and lower-back. In effect, they’re trying to shrink their bodies to be less noticed by others.

In this study, running researchers examined the MB test results and biomechanics of 80 runners. And they found distinct running-form differences between “sensing” runners and “intuition” runners. Sensing individuals are those who pay attention to physical realities and prefer practical and specific facts. Intuition individuals prefer abstract concepts and theories rather than the practical.

The sensing runners adopted “a more earthbound running form.” They had a longer contact time, and a shuffling stride. They tended to describe their running form as: “I run very close to the ground to save as much energy as possible.” 

Conversely, intuition runners “demonstrated a more dynamic and elastic running form.” They had a short contact time, and bounced upward. They tended to describe their running form as: ““I spend energy to fight against gravity because I can use my leg springs to recover energy from each step.”

The study protocol did not include a measure of actual running economy to see which personality-driven system worked more efficiently. Also, the researchers sounded disappointed that they uncovered only this sensing-intuition difference among runners from the 4 Myers Briggs types. The other three produced no significant differences in running form.

Conclusion: “This exploratory study offers compelling evidence that personality traits, specifically sensing and intuition, are associated with distinct running biomechanics.” You run as you think. More at PLOS ONE with free full text.

We Need (And Are Getting) Better Knee Therapies

Every veteran runner has experienced knee pain at some point or another. This usually isn’t terrible news--it doesn't cause arthritis or demand surgery in most cases. But it’s troubling and frustrating at the least. No one wants to run with knee pain. We aim to run smoothly, without discomfort.

The medical world would like to help us, not that there are any miracle cures. Here, a group of physicians reviews the last 23 years of progress in the field of knee health. They aim to identify the best emerging techniques, and those likely to yield good results in the near future. 

Conclusion: There’s plenty of room for improvement. Research hotspots include “hip-knee joint strength and core strength, lower limb kinematics and biomechanics, female (runners), muscle activation, risk factors, gait retraining.”

Key areas include “the clinical effectiveness of combined hip and knee strengthening to address PFPS, characterization of lower limb kinematics and biomechanics, and gait retraining.”

Future research will likely focus on “the effectiveness of innovative exercise therapies such as blood flow restriction training, gait retraining, and neuromuscular control training.”

Also, gait retraining holds potential for female runners in particular, and “a novel PRP formulation” could provide a breakthrough in knee injury treatment.  Some recent studies have suggested that PRP (platelet rich plasma) injections work better to restore knee health than other injections. More at Frontiers in Medicine with free full text.

SHORT STUFF You Don’t Want To Miss

>>> Help Sara Hall hit her goal: Boston Marathon is my 41st Birthday and I'll be committing the race to raising money for The Hall Steps Foundation and microloans to extremely poor individuals in Ethiopia. I will be personally matching all donations until I hit my goal!

>>> Get stronger now: How deadlifts can improve your running and injury protection

>>> Weight loss for real: A cardiologist explains how to lose 10 pounds over several months. (No special diet required.)  Also, from meta analysis: You need to cut calories, exercise more, focus on protein.

>>> RunTok instead of TikTok: TikTok too much for you? (Yes!) Then try RunTok for running-only content (article link). Direct link to RunTok.

GREAT QUOTES Make Great Training Partners

“Run like hell, and get the agony over with.” 

-- Clarence DeMar, 7-time Boston Marathon winner